/**
 * jQuery.labelify - Display in-textbox hints
 * Stuart Langridge, http://www.kryogenix.org/
 * Released into the public domain
 * Date: 25th June 2008
 * @author Stuart Langridge
 * @version 1.3
 *
 *
 * Basic calling syntax: jQuery("input").labelify();
 * Defaults to taking the in-field label from the field's title attribute
 *
 * You can also pass an options object with the following keys:
 *   text
 *     "title" to get the in-field label from the field's title attribute 
 *      (this is the default)
 *     "label" to get the in-field label from the inner text of the field's label
 *      (note that the label must be attached to the field with for="fieldid")
 *     a function which takes one parameter, the input field, and returns
 *      whatever text it likes
 *
 *   labelledClass
 *     a class that will be applied to the input field when it contains the
 *      label and removed when it contains user input. Defaults to blank.
 *  
 */
jQuery.fn.labelify = function(settings) {
    settings = jQuery.extend({
        text: "title",
        labelledClass: ""
    }, settings);
    var lookups = {
        title: function(input) {
            return jQuery(input).attr("title");
        },
        label: function(input) {
            return jQuery("label[for=" + input.id +"]").text();
        }
    };
    var lookup;
    var jQuery_labellified_elements = jQuery(this);
    return jQuery(this).each(function() {
        if (typeof settings.text === "string") {
            lookup = lookups[settings.text]; // what if not there?
        } else {
            lookup = settings.text; // what if not a fn?
        };
        // bail if lookup isn't a function or if it returns undefined
        if (typeof lookup !== "function") {
            return;
        }
        var lookupval = lookup(this);
        if (!lookupval) {
            return;
        }

        // need to strip newlines because the browser strips them
        // if you set textbox.value to a string containing them
        jQuery(this).data("label",lookup(this).replace(/\n/g,''));
        jQuery(this).focus(function() {
            if (this.value === jQuery(this).data("label")) {
                this.value = this.defaultValue;
                jQuery(this).removeClass(settings.labelledClass);
            }
        }).blur(function(){
            if (this.value === this.defaultValue) {
                this.value = jQuery(this).data("label");
                jQuery(this).addClass(settings.labelledClass);
            }
        });
    
        var removeValuesOnExit = function() {
            jQuery_labellified_elements.each(function(){
                if (this.value === jQuery(this).data("label")) {
                    this.value = this.defaultValue;
                    jQuery(this).removeClass(settings.labelledClass);
                }
            })
        };
    
        jQuery(this).parents("form").submit(removeValuesOnExit);
        jQuery(window).unload(removeValuesOnExit);
    
        if (this.value !== this.defaultValue) {
            // user already started typing; don't overwrite their work!
            return;
        }
        // actually set the value
        this.value = jQuery(this).data("label");
        jQuery(this).addClass(settings.labelledClass);

    });
};
